Young T K, Hershfield E S
Am J Public Health. 1986 Jul;76(7):783-6. doi: 10.2105/ajph.76.7.783.
This paper reports a case-control study to assess the protective effect of BCG (bacille Calmette-Guérin) vaccination among Indian infants in Manitoba, Canada. A record of past BCG vaccination was found in 49 per cent of the tuberculosis cases, compared to 77 per cent of the controls, yielding a relative risk of 0.30. Stratified analysis, controlling for age, increased the relative risk to 0.39 (95% confidence interval 0.22 - 0.69). The preventive fraction was 44 per cent. Non-differential misclassification of exposure status could have occurred; if this was adjusted for, the relative risk would be reduced. If only bacteriologically confirmed cases were analyzed, the age-adjusted relative risk was 0.27. The protective effect of BCG vaccination in the newborn among Manitoba Indians is therefore at least 60 per cent. The implications for health policy in this population are further discussed.
本文报告了一项病例对照研究，以评估卡介苗接种对加拿大曼尼托巴省印度裔婴儿的保护作用。在49%的结核病病例中发现有过去接种卡介苗的记录，而对照组这一比例为77%，相对风险为0.30。在控制年龄进行分层分析后，相对风险增至0.39（95%置信区间0.22 - 0.69）。预防率为44%。暴露状态可能存在非差异性错误分类；若对此进行调整，相对风险将会降低。若仅分析经细菌学确诊的病例，年龄调整后的相对风险为0.27。因此，卡介苗接种对曼尼托巴省印度裔新生儿的保护作用至少为60%。本文还进一步讨论了这一人群健康政策的相关影响。
